systemc: Add support for deprecated integer report handler ids.

These are deprecated but still used in the regression tests.

Change-Id: Id59cf950fbe0530a6cdce20a256d450b243f12d3
Reviewed-on: https://gem5-review.googlesource.com/11256
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>